This invention relates to an improved electronic counter for use with incremental measuring devices of the type used for positioning or measuring the relative position of two parts of a machine or the like. The aforementioned parts may be the slide and the bed of a tooling or measuring machine, for example.
Incremental measuring devices are commonly designed to operate in several different measuring modes, generally including an absolute measurement mode and a relative measurement mode. In the absolute mode the zero point for the measurement is provided by a fixed reference mark on the measuring device, a machine zero point, and all measurements are made with respect to this reference mark. In the relative mode the zero point for the measurement is arbitrarily set at a convenient point and measurements are made relative to the particular zero point in use at any given time. Incremental angle and position measuring devices of the prior art are subject to errors introduced when the device is alternately used in the absolute and relative measuring modes.